Folding machine for glued flap boxes



y 1961 w. J. HOTTENDORF "2,986,078

FOLDING MACHINE FOR GLUED FLAP BOXES Filed March 25, 1957 e sheets-sheet 1 INVENTOR. l WILL/AM J HOTTENDORFI BY pk! A TTORNEVS y 1961 w. J. HOTTENDORF 2,986,078

FOLDING MACHINE FOR GLUED FLAP BOXES Filed March 25, 1957 6 Sheets-Sheet 2 III In E65 IN V EN TOR. W/LL/AM J HOTTE/VDORF P ZZ A T TO/PNE VS W. J. HOTTENDQRF' FOLDING MACHINE FOR GLUED FLAP BOXES May 30, 1961 Filed March 25, 1957 6' Sheet$Sheet 3 IN V EN TOR. W/LL /AM J. HOTTENDORF A 7' TORNE VS May 30, 1961 w. J. HOTTENDORF FOLDING MACHINE FOR GLUED FLAP BOXES 6 Sheets-Sheet 4 Filed March 25, 1957 INVENTOR. W/LL/AM J HOT TENDORF A TTOPNEVS May 30, 1961 Filed March '25, 1957 W. J. HOTTENDQRF FOLDING MACHINE'FQR GLUED FLAP 6 Sheets-Sheet 5 INVENTOR. W/LL/AM J HOTTENDORF AT TOPNEVS y 1961 W.'J. HOTTENDORF 2,986,078

FOLDING MACHINE FOR GLUED-FLAP BOXES Filed March 25, 1957 '6 Sheets-Slider. e

INVENTOR. WILL/AM .1 HOT TENDORF A T TORNEVS United States Patent FOLDING MACHINE FOR GLUED FLAP BOXES- William J. Hottendorf, Los Altos, Cali f., assignor to H. & C Engineering Corporation, Sunnyvale, Calif, a corporation of California Filed Mar. 25, 1957, Ser. No. 648,213

2 Claims. (Cl. 93-52) This invention relates to box folding apparatus, and more particularly to improvements in such apparatus for making glued flap paperboard containers.

There is a present day trend in the box making industry toward the manufacture of glued flap boxes and away. from the manufacture of boxes which have their side wall joint formed by means comprising tape or staples. Automatic and relatively high speed equipment for the production of such glued flap boxes has been developed. In general, such equipment comprises, in sequencer a hopper and kicker type feed means for the paperboard blanks; creasing rolls to define, or accentuate, the fold linesabout which the blank will be folded in the machine; slotting and crushing rolls to define the eventual top and bottom panels of the box, define the glue flap, and crush the glue flap and that portion of the blank to which the flap is to be secured; glue applicator means for the glue flap; right and left side longitudinally offset flapfolding means adapted to first fold one flap through 180 and to then told the other flap through 180 into overlapped relation with the first folded flap; a squaring mechanism adapted to force the leading and trailing edges of the folded blank into parallelism; continuously movable conveyor means to move the blanks from ,the hopper through the folding stations to the squaring mechanism j and conveyor and compression means adapted to move the folded blanks away from the squaringmechanisni and to maintain them under pressure until the glue has set.

i The folding machine of the present invention embodies important improvements in both the flap folding means maths squaring mechanism, it being among the essenobjects offthe invention to improve such folding The improved flap, folding means ofthe subject mamachines in. these respects for the purposeof providing t hine. comprise a pair of twist, belts, belts per se are old in this art for this purpose (see, for example, the U.S. patent tolRotdevin 992,244), However, such twist belts, as they have previously been used, are. not satisfactory for, high speed. foldingmachines which handle corrugated aperboard] blanks. The chief problem, in

volvedinthe speed handling of'such material is that of. misalignment of the edges, of the foldedblank after the top flap has been brought down, on the-glue tabflap. Such initialmi'salignnient must be. controlled within limits, as, otherwise its subsequent, correction in thes quaringmechanism may lead to' anunsatisfactory product, from the standpoints of both strength and appea riance, i.e. glue is swiped; ofl of the eventual joint area onto adjacent and. viewable areas. of. the box form.

To my} knowledge, the twist beltsT previonslyfisedT in boxfolding machines have been operated at a 121 speed ratio with the conveyor belts. Sincethese belts are angled inwardly toward the conveyor belts to perform the toldingoperation, the component of their speed parallel to the longitudinal axis of the machine is less than the-speed of the conveyor belts. Along with this, there is the further factor that the belts engage the flaps first forwardly and then progressively rearwardly during the folding operation. The net result is that the belts drag, or skew, the, flaps toward the trailing edge of the blank. In the subject machine the twist belts are driven at a sufficiently greater speed than the conveyor belts so that the component of forward movement of any point on either belt is at all times greater than the rate of forward movement of the conveyor belts. While the belts progressively engage the flaps from front to rear, and some rearward skewing of the folded flaps is produced, the amount of skewing tends to be reduced to a minimum by the forward drag imparted to the flaps by the forward speed differential between the twist belts and the conveyor belts. When the twist belts come into alignment with theconveyor belts at the end of the folding operation, i.e. whenv both sets of belts grip the folded blank between them, the relative forward movement of the twist belts with respect to the conveyor belts causes the rearwardly skewed flaps. to be dragged forwardly.

The improved squaring mechanism of the subject machine comprises a conveyor belt disposed transversely to the folder portionof the machine at the delivery end thereof, a fixed plate disposed between said belt and said delivery end and beneath the latter, a backstop plate which is reciprocably movable towardsaid fixed plate to square a box form received therebetween and away from said fixed plate to enlarge the box form receiving space. By enlarging said receiving space to receipe a box form ejectedfrom the folder. portion ofsaid machine and closing it to square the box form received, a higher speed of operation of the machine is made possible and a simpler machine is made available, as compared to thosefrnachines in which the ejected forms are required to be kicked downwardly into a relatively narrow receiving space which is'rearwardly'defined by a fixed backstop plate. In combination with this movable backstop and fixedfore-plate, the fore-plate is slightly angularly inclinecl towai-d-the backstop to'insnre that a box formbeing squaredis' urged toward the takeaway conveyor belt, and the latter: is downwardly inclinedlin its direction. of m rovement sothat the 'shingled patternof box forms under pressure thereon consists of horizontally: disposed, box form units. i 7 '7 f f 1 l Other objects and advantages of thesubject machine be apparent from the following descriptiontaken in agnetis i h he. dr win s min par ofit specification, andin'whi ch: Y I

Figure, 1 is a viewin -top plan ofthe machine; Figure 2 isf an enlarged top plan view of the squari s n fieni vms bf' hema h m Eigure 3,is1 a view in side elevation of that part of mechanism end of themachine;

Figure 8 is, aplan viewof a folded box form having misal ignedrleading.andtrailingedges; V a F e 9; is a plan view of folded box form as; it

would ar tt l ns h' l t e e ua in ma h? n n; r r

Figure is a perspective view of a folded box form; and

Figures 11-14 are detail views in section taken, respectively, along lines 11-11, 1212, 13- 13 and 14-14 of Figure 1, illustrating the positional sequence of the twist belts and the flap folding operation.

With initial reference to Figure 1, the subject machine comprises spaced apart front end side castings 10 mutually supporting therebetween: a hopper table and slide support 11 adapted to support both box stock 12 and kicker means 14, the latter being operable to repetitively feed the lower sheets of the stock into the machine; feed rolls 16 adapted to pull the sheets, or blanks, through the feed end of the machine; a shaft 18 carrying blank scoring rings 20 and a trim knife 22; a shaft 24 carrying crusher rolls 26 and 28 for the blank portions to be glue-lapped, glue flap cutting means 30, and slotter means 32. The kicker means 14, feed rolls 16 and shafts 18 and 24 are operated in timed relation with each other through a speed reducer, not shown, by motive power means, not shown, said means also operating through said speed reducer to drive a line shaft 34 in timed relation to said kicker means 14, feed rolls 16 and shafts 18 and 24. A glue applicator roll 35 is disposed in line with the glue flap crusher 26 and is .adapted to apply glue to the undersides of the crushed flaps of the blanks.

Disposed in blank receiving relation with the feed end of the machine and adapted to grippingly engage the blanks before they have fully passed through the feed rolls 16 are a pair of rubber-covered conveyor belts 36 and 38 and a pair of sets of rubber covered rollers 40 (Figures 11-12). The belts 36 and 38 are supported on roller members 42 rotatably carried by elongated channel members 44 which are disposed for lateral adjustment with respect to each other. Said conveyor belts 36 and 38 are trained around idler rolls 46 (Figure 3) carried by rear end side castings 48, driver roll 50 secured to shaft 52 journalled for rotation in castings 48, guide rolls 54 depending from channel members 44, and idler rolls 56 (Figure 11) carried at the forward ends of the channel members 44. The sets of rubber covered rollers are journalled for rotation in channel members 58 which are supported by brackets 60 suspended from cross rod means 62 forming part of the head frame of the machine. The roller-bearing channel members 58 terminate at 64 (Figure 1) and they are succeeded by fixed bar members 66 (Figures 1 and 13) which terminate at 68. The rollers 40 serve as hold down means and fold-guide means for the blanks until the folding of the flaps 70 and 72 of the blanks 74 approaches 90. Thereafter the bar members 66 serve as hold down means and fold-guide means until the folding of the flaps approaches 180. Thereafter the twist belts 76 and 78 complete the folding operation and serve as the hold down means for the blanks.

The twist belts 76 and 78 are trained around idler rolls 80 (Figures 1 and 11) carried for rotation by the channel members 44 adjacent the forward ends thereof and around driver rolls 82 fixedly secured to shaft 84 which is journalled for rotation in the castings 48. The flap folding reach of belt 76 is twisted through an angle of 180 by guide means mounted on the adjacent channel member 44 comprising an angularly disposed roller 86, cone shaped roller 88, and horizontally extending roller 90. The return reach of the belt 76 is reversely twisted through an angle of 180 by the cone shaped roller 88 and an angularly disposed guide roller 92 carried by the channel member 44. The flap folding reach of belt 78 is twisted through an angle of 180 by similar guide means mounted on the adjacent channel member 44 comprising angularly disposed roller 94, cone shaped roller 96, and horizontally extending roller 98, and the return reach of this belt is reversely twisted through 180 by the cone shaped roller 96 and an angularly disposed guide roller 100, but these 'guide means for belt 78 are located closer to the delivery end of the machine than are the corresponding guide means for belt 76, thereby enabling the latter to fold the edge of the blank. the rate of travel of the twist belts and the lower conveyor glue containing flaps 70 of the blanks 74 before the flaps 72 thereof are folded by belt 78. A pair of horizontally disposed idler rolls 102 carried by channel members 44 and provided with concave peripheries are adapted to engage the edges of the twist belts for aligning and guiding the belts.

The twist belts 76 and 78 are driven in timed relation to the lower conveyor belts 36 and 38 by means comprising: line shaft 34; bevel gear 104 carried by shaft 34; bevel gear 106 secured to shaft 52 and in mesh with gear 104; sprocket 108 (Figure 3) secured to shaft 52; a chain 110 trained around sprocket 108 and around a sprocket 112 secured to a stub shaft 114 carried for rotation by a side casting 48; a gear wheel 116 removably secured to stub shaft 114 in a position outboard of sprocket 112; and a gear wheel 118 fixedly secured to shaft 84 and in mesh with gear wheel 116. The speed ratio between the conveyor belts 36 and 38 and the twist belts 76 and 78 is controlled by the proper selection of gear wheel 116 as to its size and the number of teeth on it. For eflicient high speed operation of the subject machine, the gear wheel 116 is so selected as to cause the twist belts 76 and 78 to have a speed component in a direction parallel to the paths of movement of the belts 36 and 38 which is slightly greater than the rate of travel of the belts 36 and 38.

The twist pattern followed by the belts 76 and 78 is such that the belts engage the leading edge of the blank flaps to be folded and thereafter progressively increase their engagement with the flaps in the direction of the trailing edges of the flaps until the belts engage the flaps full length at the end of the folding operation (Figure 14). This progressive front to back engagement of the belts with the flaps tends to cause the flaps to be skewed toward the trailing edge of the blank despite the fact that those portions of the belts engaging the flaps have a greater rate of movement longitudinally of the machine than the blanks themselves which are being moved at the rate of travel of the lower conveyor belts 36 and 38.

However, this speed differential between the twist belts and the lower conveyor belts tends to reduce the degree of rearward skewing of the flaps.

The skewed condition of the folded blanks as it appears as soon as the blanks have been folded by the twist belts is illustrated in Figure 8, with the upper edges of blank being the leading edge and with the lower edge being the trailing edge. Immediately thereafter, the twist belts 76 and 78 come into parallelism with the lower conveyor belts 36 and 38 and are pressed against the blanks by the guide rollers and 98. The effective speed differential between the twist belts and the lower conveyor belts then becomes increased, and this, together with the fact that the twist belts grippingly engage the blanks after passing the guide rollers 90 and 98, causes the folded flaps to be shifted toward the leading end of the blank to substantially eliminate the skewed condition illustrated in Figure 8. In fact, any given blank may have the Figure 8 skewed condition not only eliminated but may have the flaps thereof skewed slightly in the direction of the leading In any event, the difference between belts causes an undesirable condition, caused by the twist belts, to be cured by the twist belts preliminary to the ejection of the blanks from the machine into the squaring mechanism hereinafter described.

In practice, the over speed of the twist belts with respect to the lower conveyor belts has been 3.7 inches per revolution of the slotter roll bearing shaft 24. A

blank is introduced into the machine for each revolution of shaft 24. When shaft 24 is operated at its maximum speed of 300 r.p.m., i.e. when the machine is gluing box forms at its maximum capacity of 18,000 per hour, the twist belts are running at the rate of 1396 feet per minute and the lower conveyor belts are running at the rate of 1302 feet per minute. At all times, every point on the twist belts has a speed component measured in a direction parallel to the longitudinal axis of the machine which is gamma statesman the. 2. t erm n fi u r e ow r P YYQ b gl ed. b n ar e t m e e pp r andlower belts onto a conveyor belt 122 which is trained about a drive roller1 2 4 and an idler roller 12 6 and has its upper reach supported by a plurality of spaced rollers 128 (Figure 7). The rollers124-128 are journalled between cross frame members 130 and 132 whicharesecured to the side castings 48. The blanks ejectedfrom the machine onto the conveyor 122 are kicked forwardly in their direction of movement by engagement with the undersides of a pair of rubber wheels 130. These wheels lggtl are fixed to stub shafts 132 which are rotatably carried by brackets 134. Brackets l 34are freely sleeved onshaft 84 and their outer ends are supportedly suspended from frame cross bar 136, as by chains 1 38. Belt drives 140 trained around sheaves fixedly secured to shaft 84 andto the stub shafts 132cause the shafts l3 2and the rubber wheels 130 canied therebyto be rotated at, a speedconsiderably in excess of the speed of rotation of shaft '84: l

After the blanks have been kicked forwardly by the rubber wheels 130, they are deflected downwardly against a backstop plate 142 by a shoe 144 which is supported by a cross bar 136. The plate 142 is fixedly secured to end support members 146 and 148. The support members 146 and 148 have a dovetail connection (Figure 4) with the upper ends 150 of slide members 152 and 154. Slide members 152 and 154 are slidably sleeved on rods 156 which are secured to frame cross members 158 and 160. Means to move the slide members 152 and 154 on the rods 156 comprise a pair of eccentrics 162 secured to shaft 52, pitman arms 164 sleeved on the eccentrics 162, and arm members 166 secured to the slide members and having a pivotal connection with the pitman arms 164. During each rotation of shaft 52, the slide members 152 and 154 are moved from their solid line position shown in Figure 5 to the dotted line position shown therein and back again to the solid line position. The backstop plate 142 is similarly moved, as means are provided to secure the same in any desired position of adjustment with respect to the slide members 152 and 154. Such means comprise (Figure 4) toothed racks 168 formed in the upper ends of the slide members 152 and 154, gear wheels 170 fixedly secured to a set shaft 172 journalled for rotative movement in the backstop plate support members 146 and 148, said gear wheels 170 being in mesh with the racks 168, and set nuts 174 secured to the threaded ends of shaft 172 and adapted to clamp the shaft to the support members 146 and 148 to prevent accidental rotation thereof. When the nuts 174 are loosened, the shaft 172 may be selectively rotated to adjust the backstop plate 142 to the desired position on the slide members 152 and 154, the desired position being that in which the distance between the backstop plate 142, at the end of the inward stroke thereof, and fixed plate 176 carried by the side castings 48 corresponds to the squared width of the box forms to be squared therebetween.

The reciprocating movement of the backstop plate 142 is timed with that of the feed kicking means 14 which is adapted to feed the undermost blank of the box stock 12 into the machine on its forward stroke. As the kicking means 14 begins its forward movement, i.e. when the folded blank at the end of the folding machine commences to be ejected therefrom, the backstop plate 142 commences its rearward movement. When a folded blank is ejected from the machine, accelerated by the rubber wheels 130, and deflected downwardly by the shoe 144, the backstop plate 142 is still being moved away from the fixed plate 176. The leading edge of the blank projected onto the conveyor 122 strikes the backstop plate 142 while the latter is still moving away from fixed plate 176, and this movement of the blank and the plate 142 in the same direction cushions the impact imparted to the blank by the plate, thereby preventing any damage to h bl nk- Ma e, m q antly la ks a e. p otected ntoa wid ni g n gs. define 'hetwee the mqvin ba ston lat 4234 2141 1? xe Plat 761-. i e able th mash ng o. be o erat d] a he r dsp' bu ly en ione a ers s asna im a on fa tor s c a wi e lobe con en ed i h i v the p e, 13. er e nd. e te 76 wer ms 'b o n d, as tau h by the state ofthe prior art. Furthermore, it is not necessary to VigOIZOtISlYJdefleCt, or bend, the blanks issuing from thefolding machine downwardly so that they maybe fitted into the receiving space ofthe squaring mechanism. Such vigorous handling of the blanks subjects them to strains which may be, reflected when they areput to eventual use. i v

After the leading edges f the blanks strike the plate 142'and the trailingends of the blanks drop onto the conveyor belt 122, the backstop plate 142 commences its re; turn stroke to bring theftrailing edges of the blanks into engagement with the face of the fixed plate 176, thereby removing any misalignment" from both the leading and trai-ling dges.

Each blank delivered to the conveyor 122 is brought up against the plate 176 many times during the course of its passage along the conveyor, as indicated by the shingled condition of the plurality of blanks on the conveyor in Figure 7. The shoe 144 presses against the stacked blanks on the conveyor 122, thereby tending to hold the stack of blanks against the plate 176. The angular disposition of the conveyor 122 causes the blanks of the shingled stack to be horizontally disposed, as shown in Figure 7, in which position they may be best subjected to initial compression offered by sets of presser wheels 178 which engage the tapered advancing front of the shingled blanks. The sets of wheels 178 are slidably supported by hanger means comprising a support bar 180, sleeves 18 2 and set bolts 184.

The squared blanks pass from conveyor 122 onto conveyor belt 186 which is trained around an idler I011 188, and a driver roll 190, and which has its upper reach supported by a plurality of support rollers 192. The conveyor 186 is upwardly inclined in its direction of movement, and a plurality of pressure wheel sets 194 adjustably supported on one or more support bars 196 is provided to maintain the blanks under compression while the glue joints become set, or substantially set. A further conveyor in receiving relation to conveyor 186 and having associated therewith secondary compression means to maintain the blanks under a holding pressure until the glue joints have fully set may be provided.

The conveyor 186 is driven by motor 198 having a sprocket and chain connection, indicated generally at 200, with the shaft which carries driver roll 190. A sprocket and chain connection, indicated generally at 202, interconnects the shaft carrying idler roll 188 for conveyor 186 and the shaft carrying roll 124 of conveyor 122.

It will be noted (Figure 5) that the face of the fixed plate 176 of the squaring mechanism is very slightly angularly inclined toward the conveyor belt 122, thereby insuring that the blanks will be squared in parallel relation to the conveyor belt.

What is claimed is: V

'1. In a box folding machine, a sub-combination adapted to fold the flaps of a box blank which has been scored and slotted and which has defined therein a glue flap to which glue has been applied, said sub-combination comprising continuous belt means to convey said blank along a horizontal path, a pair of alike and continuous twist belts, one for each flap to be folded, having forward and return reaches, movable support and guide means for each of said forward reaches constraining the same to twist through angles of from positions in which they underlie the flaps to be folded to a position in which they overlie and are parallel to said continuous belt means and grippingly engage said flaps after they have been folded, movable support and guide 7 7 means for each of said return reaches constraining the same to reversely twist through angles of 180, and means for driving said continuous belt means and said twist belts in timed relation including means for causing said twist belts to move at a slightly greater speed than said continuous belt means, whereby any rearward skewing of said folded flaps will be decreased by said twist belts.

2. In a box folding machine, a sub-combination adapted to fold the flaps of a box blank which has been scored and slotted and which has defined therein a glue flap to which glue has been applied, said sub-combination comprising first belt means to convey said blank along a straight horizontal path, with said flaps to be folded being disposed outwardly of said belt means, means for sequentially folding said flaps through 180 and for decreasing rearward skewing of said flaps including second belt means extending into parallel overlying relation with said first belt means after said flaps have been folded and being adapted to grippingly engage said folded flaps, and means for driving said first and second belt 20 2,823,594

References Cited in the file of this patent UNITED STATES PATENTS 992,244 Potdevin May 16, 1911 1,318,910 Pfohl Oct. 14, 1919 1,454,924 Halvorsen May 15, 1923 1,581,583 Low Apr. 20, 1926 1,792,693 Johnson Feb. 17, 1931 1,949,881 Potdevin Mar. 6, 1934 2,142,011 Spiess Dec. 27, 1934 2,589,944 Labombarde Mar. 18, 1952 2,599,442 Essex et al June 3, 1952 2,637,251 Spiess May 5, 1953 Fischer Feb. 18, 1958 

